1. Technology Field
The present invention relates to a non-volatile memory storage apparatus, a memory controller and a data storing method, which are capable of writing data stored temporarily in a buffer memory into a non-volatile memory module of the non-volatile memory storage apparatus when the power supply of the non-volatile memory storage apparatus is disconnected unexpectedly.
2. Description of Related Art
The markets of digital cameras, cellular phones, and MP3 players have expanded rapidly in recent years, so that consumer demand for storage media have also rapid increased. Rewritable non-volatile memory is one of the most adaptable memories for battery-powered portable products due to its characteristics such as data non-volatility, low power consumption, small volume, and non-mechanical structure. A flash drive is a storage apparatus adopting NAND flash memory as storage medium. For example, through a universal serial bus (USB), users can easily plug a flash drive into a host to deliver digital data.
Because the speed of writing data into a flash memory module is far lower than the transmission speed of the USB coupled to a host, in general, a buffer memory may be disposed in the non-volatile memory storage apparatus for temporarily storing data from the host. In particular, when the host gives a write command and data to be written to the non-volatile memory storage apparatus, a memory control circuit (also referred to as a memory controller) replies a message indicating that the write command has completed to the host after temporarily storing the data in the buffer memory, thereby enhancing the performance of the non-volatile memory storage apparatus.
However, the flash drive has to operate with a power supplied by the host through the USB. Therefore, if data is stored temporarily in the buffer memory and a user removes the flash drive from the host, the data will be lost. Thereby, when the power supply of the non-volatile memory storage apparatus is disconnected unexpectedly, how to reserve data stored in the buffer memory is one of the major subjects in the industry.
Nothing herein should be construed as an admission of knowledge in the prior art of any portion of the present invention. Furthermore, citation or identification of any document in this application is not an admission that such document is available as prior art to the present invention, or that any reference forms a part of the common general knowledge in the art.